It’s been about a year and a half since I officially became a father. I put the official qualifier there because I knew I was going to become a father about two years ago, and many of the psychological changes probably began then. My own reflections and lessons are obviously influenced by my own specific situation. I am not the primary caregiver. It would be too pat to say that our family is the typical college educated sort in all its details, but it is not that far from the truth. My daughter, and her parents, have resources, both financial and familial, which are not there for about half of Americans. I obviously can’t speak to the struggles of working class single mothers. And the American class system being what it is I can’t say I know any such women very well beyond the level of tenuous acquaintanceship.

The first reflection I want to admit is that it is one thing to assert the power of hertability in the abstract, and another to see it in the concrete. It is easy enough to do a scatterplot of a quantitative trait like height. But at very young ages of much more salience are mannerisms and other less quantifiable behavioral tics. It was immediately obvious within the first month of her life that my daughter has some of her parents’ idiosyncratic habits. To give an example there is a way I pick my fingers, in particular my thumb, without even thinking about it. I share this trait with my mother. My daughter began to exhibit the same behavior in her sleep when she was less than one month old. Similarly, there are a variety of body movements where she reminds me a great deal of my youngest brother…but that is perhaps more a function of the fact that he is the one with whom I share the most in terms of biomechanical affect.

Probably one thing that helps keep my inferences and pattern matching in context and in check is the fact that I’ve read The Nurture Assumption. The central observation of this book is that only about ~10% of differences between children on behavioral traits seems to be due to unique parenting strategies and tactics. In other words, your choices as a parent don’t matter nearly as much as you think. It turns out that about half the remaining variation is due to the genes you contribute, and the other half is unaccounted for. To many of you this may seem a trivial insight, but it isn’t. Our media is saturated by arguments at the heart of which is the assumption that the role of parents is central to the development of our children. The current fad for attachment parenting is a case in point. All of these cultural currents hook into the reality that as parents you do agonize often about the most minor details of your child’s upbringing, and what effects that might have in the long term. This makes sense to be, as much of life is a positional game. I have no reason to doubt that this wasn’t true in the past, in which case the marginal impact of parenting on the individual level may have been quite significant. 10% might not seem like so much, but that’s the difference between a B+ and an A+!

Click to enlage

But the major problems with this assumption of the centrality of parental behavior and modeling crop up when you assume they are incredibly causal on a broader social level. This article in The Atlantic is typical, The Distinct, Positive Impact of a Good Dad. Before disputing some of the interpretation of the data I want to admit that all things equal I believe it is better to have two parents than just one. The problem is that not all things are equal. If you click to enlarge the infographic you will see that it states that “An asterisk (*) indicates a statistically-significant difference (p < 0.05) indicated between the group and those who scored in the top third of relationship quality with their father, controlling for respondent’s age, race/ethnicity, level of mother’s education, and household income.” There is one control I do not see listed there: genetics.

A stylized example will illustrate the problem as I see it. Imagine a random sample of 18 year old women who become pregnant by their boyfriend. Half of the boyfriends refuse to help support the child or enter into a lasting relationship, while half of them do so. After 10-20 years you tally the outcomes of the offspring, and you see that those whose fathers remained active in their lives had far better life outcomes when measured on broad metrics of social dysfunction such as delinquency. One inference you could make is that the environment fathers provide is essential toward stabilizing the home and allowing their children to flourish. That is the conventional conclusion that is normally made both in public and private. And, that is why you control for facts such as mother’s education and income in the result above.

But if you think about it closely you see a rather obvious assumption in the model: that the genetic dispositions of the men who abandoned and those who did not abandon are the same. The sort of “man” who would abandon the mother of his child and his child is likely to have a disposition which will be passed down toward his children, even in his absence. The main blind spot with the idea that “family values” is a panacea for all of our problems is that proponents often give nurture all the credit, and don’t even consider the possibility of heritable dispositions. Behavior genetic work tends to point to the possibility that in fact these heritable dispositions strongly effect life outcomes. Fathers matter, but for rather diverse reasons. Neither his sperm nor his magical presence explain it all.

And yet please remember that a huge fraction of the variation is not accounted for. It doesn’t seem to be straightforwardly heritable, nor is it due to distinct home environment. Judith Rich Harris in The Nurture Assumption proposed that much of the “non-shared environment” was peer group. A simple illustration of the dynamic has to do with accents. Children usually speak with the accent of their peer cohort, not that of their parents. But the reality is that we still don’t know what this non-shared environmental component of variance is. In fact it could be gene-gene interactions, which won’t get captured by measures of heritability. Or it could be developmental stochasticity. I bring these up to point out that even if less than half of the variance of the trait in the population is due to genes that does not entail that it is particularly amenable to reshaping via social policy. Secondarily, even highly heritable traits, such as height (~80% of the trait variation is due to genetic variation) exhibit only mild correlations when you look across siblings (r ~ 0.50 for height). So lesson two: children are going to vary, and you may not have much control over that variation.

Ultimately what my daughter has taught me as a father intellectually in regards to raising her is that I always have to update my assumptions and beliefs, and allow her to give me input into her own development. I don’t subscribe to any major “school” of parenting, nor do I think there is a one-size-fits-all model which would be appropriate for the majority of children beyond the basics (i.e., feed your children adequately and prepare them for the expectations of society as a whole). But natural and social science does give me broad parameters, setting the horizons of the landscape. And yet the space of possible choices is still enormous. For me my daughter is a sort of personal tachyon, her existence is so absorbing that I have a hard time viscerally recalling when she did not exist. And I wouldn’t have it any other way. But that’s feeling, not analysis. And sometimes that is the point!

A common understanding of the concept of the sociologist’s fallacy would immeasurably improve public dialog on a number of important issues. It’s a shorthand abstraction that needs promoting, but unfortunately I have never seen the term even mentioned in the mainstream press.

https://delicious.com/robertford Robert Ford

I think you should start her off by getting her Google Glass with a ScienceDaily RSS feed going. Just to see what happens!

https://twitter.com/Sheril_ Sheril Kirshenbaum

1) I especially like your closing point.

2) It will be so nice to teach our kids code together.

3) Happy Father’s Day Razib!

Sandgroper

Seeing bits of myself at different ages in my daughter as she grew up made it impossible not to remember myself with a different perspective than before she existed.

Sandgroper

It does get progressively more disappointing, though – you got an artwork original, presented in person by the Artist. I got a cut and pasted cartoon of a duck emailed from 4,000 miles away.

Andrew Selvarasa

Although I am 26, and am single with no children, I empathize with this article due to the fact that my brother is 7 years, 8 months and 18 days younger than I am. The large age gap has allowed me to relive stages of my life that I only recently have exited. Other than the striking height, weight and phenotypic similarities, our IQs, EQs, hobbies, morality and ideals are exactly the same. I notice little idiosyncrasies in him that I was previously unaware existed in myself. People joke that we’re MZ twins born years apart.

I often wonder, if there were three of us, if the third sibling would be just like us, or different enough to represent the normal differences you see between most siblings.

razibkhan

have two brothers ~5 and ~15 years younger than me. didn’t grow up with the latter, but he’s the one who resembles me more physically an in terms of beliefs/orientation.

Andrew Selvarasa

I remember you mentioned a while back that you have one sibling (sister?) who you share ~45% of your genome with, and another sibling (brother?) you share ~55% with? And one of your brothers — the more robust in frame — has the most Neanerthal ancestry?

I’ve been reading you since grade 12 in 2003, so I may be mixing up articles!

razibkhan

yeah

MrJones

“proposed that much of the “non-shared environment” was peer group.”
This would mean controlling peer group was a large part of parenting.
I wonder if the peer group thing is partly or largely modern and due to lengthy education where that applies. In a weaver family where the kids worked with the parents as soon as they were old enough i wonder if parents / family were the peer group?

razibkhan

This would mean controlling peer group was a large part of parenting.

that is a major argument in the book.

Also I wonder if the peer group thing is partly or largely modern and due to lengthy education where that applies. In a weaver family where the kids worked with the parents as soon as they were old enough i wonder if parents / family were the peer group?

no to parents. high parental mortality rates. family = cousins, would be the peer group though….

Linda Seebach

Home schooling is in significant part a matter of controlling a
child’s peer group; home-schooled students spend much less of
their time in age-segregated classrooms and are less likely to
feel that only agemates are peers. (Not the only difference,
obviously, but one less often remarked upon.) Colleges report that
they often seem more mature, which may mean merely that they are
more adult-oriented. (Sorry, I don’t have a cite handy; but a
friend who worked in college admissions once told me that was why
his college favored home-schooled applicants, not just that they
were better prepared academically.) But parents who choose to
home-school are atypical in other ways, too, so who knows?

Pollo Asado

Kids also have a way of throwing your negative traits (e.g. stubbornness, temper) back in your face when you get to see a little mini-you acting the same way you’re prone to act. It’s humbling.

chris_T_T

Raising a child is quite the humbling experience. My own son will be two in a less than a month and it has been an amazing ride.

Besides peer group, parents also have considerable control over what opportunities a child is exposed to. It’s important to expose them to and let them try many different experiences early on. We may not be able to control what they’re innately good at and enjoy, but we can help them find what that is.

Euler

“But the reality is that we still don’t know what this non-shared environmental component of variance is. In fact it could be gene-gene interactions, which won’t get captured by measures of heritability.”

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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at http://www.razib.com